Are hot spots coming back? Home sales and prices in a number of Sun Belt cities showed rapid improvement over the past year amid an ongoing recovery in the overall U.S. housing market. Many of the gains enjoyed by Sun Belt cities -- including Phoenix, which led the way with a nearly 30% year-over-year rise in its median home price in 2012 -- are due to the inevitable rebound that happens after a market collapses. Housing markets also benefited from